I received so many compliments on this dress. I am 5'1 and weight 124 lbs. I ordered a size 4 and it fit comfortably. I didn't have a need to use spanx and believe me - my body isn't perfect. I received great compliments on this dress. I strongly recommend purchasing! It's versatile to wear for multiple cocktail functions.
I originally purchased a size 6 and a size 8. Unfortunately, neither fit. Ended up having to order a 10 & 12. The 10 fit great, just had to get it taken in around the chest. I am 5'7", 150 pounds with a B chest. I recommend going a size up than you normally would to get the optimum fit. Very flattering once the right size works.